Defender 2.5 Petrol engine, what's it like ??

[Smokydiesel]

Hi,

I had a look at a 1984 Defender 90 today, it is fitted with the 2.5 petrol engine.

So, what's this engine like, performance wise ?

and what about the noise levels ?

I already have a Defender 200 TDI (retro fitted).

I like the TDI engine for it's pulling power, but hate the noise it makes at motorway speeds (even with soundproofing fitted)

Would the 2.5 petrol pull a horse box uphill ?

Thanks for your replies !

Edwin

[farmerboy_y2k]

My 1st 110 was a 2.5P i don't remember it being much quieter than my current 200tdi. (My tdi isn't that noisy, can listen to the radio or have a conversation easily at 70mph).

You'll certainly notice how much less power it has 83bhp vs 107bhp for defender 200tdi. and torque is down to 133lbf.ft from your tdi's 188lbf.ft. Part of the reason I sold mine was the engine was well worn and would struggle on steep hills never mind towing and even converted to lpg, 14mpg didn't make it cheap to run.

[discomikey]

id keep the TDI, the petrols can be a bit quieter but youll find yourself in maybe 2nd goijng up some hills where 4th would do with a TDI

if i were you id look into better soundproofing, although i do like the sound of the engine, that sort of distinct chugga chugga chugga chugga

[Quagmire]

My 90 used to have a 2.25 in it- now has a v8. The 2.25 was a good reliable engine but did not pick up speed too well! Was fine once you were cruising, until you got to a hill. Sound was fine- better than a diesel

I imagine the 2.5 is the same but a tad better. At the end of the day I fitted the 3.5 for a reason and haven't looked back! A 200tdi should kick the 2.5 petrol's bottom easily...

[discomikey]

my 200 needed the extra gearing or soundproofing compared to the 2.25p, i chose gearing first as with standard diffs and no overdrive it screams at 45 with a TDI, with diffs and O/D it loves 60/70 +

[tacr2man]

The 2.5 petrol with a bit of modding could equal/pass the 200 tdi , i.e carb and up the comp ratio, electronic ign . It will pull uphill as it is but just a bit slower. NL only has one hill IIRC with a big radio mast on it ( I camped there in my 109 about 30+years ago ) so are you taking your horsebox further afield ?

[farmerboy_y2k]

The 2.5 petrol with a bit of modding could equal/pass the 200 tdi , i.e carb and up the comp ratio, electronic ign .

Taking a 2.5p to 2.8, stage 2 head, uprated cam and SU carb gets to 117bhp and 177lbf.ft so bit more power but still less torque and further up the rev range And it will still drink petrol at a fair rate. A well set up V8 would be a better option than a 2.5 imo. But i'd have a tdi over either.

[tacr2man]

I can put up with a tdi for the economy , but I have to drive the V8 to get my fix , untill I refuel , and remember why I also have the tdi

[Mo Murphy]

2.5 petrol - all of the fuel economy of a V8 with none of the performance !

Mo

[Jim1]

My 2.5 petrol only did 15 to the gallon, lack of power then blow 2 pistons changed it to 300tdi

[UdderlyOffroad]

I drove my 2.5 for a few months before it ran out of MOT & I started the rebuild+conversion to a diesel.

Slowy, noisy, thirsty...I loved it - nainly because I finally had a landie. And yes, I (slowly) pulled 2ton trailers uphill without incident. But let's be clear, it will not be an improvement over your 200Tdi.

If it must be petrol, V8+LPG. Otherwise, soundproof your diesel. Seatbox, floormats, underbonnet, all will help.

[UdderlyOffroad]

Just re-read your OP and realised you already have sound proofing fitted...fit more anyway! ;-)

But if noise at motorway speed is the problem: what gearing & tyres do you have fitted? Have you considered a discovery transferbox or Ashcroft gearset?

[vulcan bomber]

Have you considered a discovery transferbox or Ashcroft gearset?

A different kettle of fish on a petrol..

[CwazyWabbit]

A different kettle of fish on a petrol..

He's referring to the diesel. The OP has a 200tdi and is it appears only considering a petrol due to the noise of the 200tdi on the motorways. Hence the gearing change suggestion to quiten motorway speeds by reducing revs.

[vulcan bomber]

He's referring to the diesel. The OP has a 200tdi and is it appears only considering a petrol due to the noise of the 200tdi on the motorways. Hence the gearing change suggestion to quiten motorway speeds by reducing revs.

i knew that............

In my experiance, a 1.2 box on a defender is horrid, other people say other things, so if you can try it before you do it.

[CwazyWabbit]

i knew that............

In my experiance, a 1.2 box on a defender is horrid, other people say other things, so if you can try it before you do it.

In which case buying a RoverDrive or similar could give you the best of both worlds.... although they cost a significant amount of the folding stuff

[vulcan bomber]

In which case buying a RoverDrive or similar could give you the best of both worlds.... although they cost a significant amount of the folding stuff

Yes they do, however I'd go for (indeed i'm saving funds for one now) an over drive every time now.

[mark-d]

thought it would be a 2.25 in a 84? mine is a 2.25 on an 85

I find it ok around town and off road but it does struggle up hill abit when on motorways.

and it drinks fuel, far to much for my liking so a 200tdi will be going in mine

[rusty_wingnut]

In my experience the 1.4 of the Tdi is perfect for everything, the 1.2 is just to much for it and doesn't make for an acceptable drive (even with the pump and turbo turned up).

I have a 3.9 V8 now with a 1.2 and 235 85 tyres and this is a far better combination, I can safely tow another land rover on a twin axle at the regulated 60mph without trying hard. I am also get half decent economy with it, it is worse than my old 300, but petrol is cheaper and frankly having driven a V8 and had the performance I cannot begin to fathom going back to a slow diesel.

I would try having the head skimmed on the 2.5, as well as a decent manifold and an SU carb with electornic ignition. This will improve it no end, improving power and efficiency in the process.

[honitonhobbit]

Real world answer

2.5 is a nice lump BUT hugely stiffled and massively over engineered. It's easy to tune if you understand petrol, but then a 200Tdi is even easier to tune...

SU carb and side draft conversion

10thou off the head

Valves re-seated

Ported

DON'T POLISH THE INLET MANIFOLD

Better exhaust

Lighten and balance flywheel

Lighten, balance and toughride the crank

12% NOS from 1200rpm

But why go to this level of work?

Standard is about 88bhp when new, you can (without the NOS) run it up to about 130 before a 2.8 stroker kit but it's all in the wrong place unless you chuck it in a lightened racer

NOS is fun though - more fun in a 200 mind

[BogMonster]

2.5 petrol - all of the fuel economy of a V8 with none of the performance !

Unfortunately more or less right. A lovely engine off road which you can take down to about 500rpm without stalling and it picks up instantly at low rpm, but feels like a fish out of water on the road by any modern standards. I like the engine a lot, and I used to own one, but it's a nostalgic fond memory sort of like, not an "I want to own one again" sort of like....

[oddballrovers]

HI

We run one in The Kitten, it is a 88" LWT weighing 1550kg combat ready (6 point roll-cage 4 waffleboards and much more), gearbox is One Ton so pretty low geared.

In that car it is a fine match and we are within regs, but fuel ecnomy is as V8, max speed is 55mph due to the low gear, it is a nice old school engine easy to fix and so,BUT in anyting but a 88" I would not recommend it, it is though a very fine upgrade in a 88".

Thats just my 5´p

Regards

Ole

[DavidW]

I've recently replaced mine with a disco 200tdi.

Mine was in pretty good health and doing about 16mpg. I find the 200tdi a much more relaxed, easier and faster drive for every day use.

When pulling things the petrol will always get you there, you're just going slower in a lower gear.

Don't discount buying petrol with a view to changing at sometime. If found it worked financially for me.

David

[LCJ]

I ended up buying a 1993 2.5 Petrol 90 because a) it was LEZ compliant and b) the rest of the vehicle was in much better condition than any diesel model I could find for the same money.

I'm now pretty bored of the petrol engine - not because it's appallingly slow (although it cant be described as lively) but simply because of the fuel economy. As a result it's 200tdi time I think. I'm considering going to Glencoyne, but would rather have the work done locally - can anyone recommend someone in Surrey who could source the engine and do the conversion as well as Glencoyne seem to?

To answer the OP - I'd buy it if the rest of the vehicle was up to scratch and fuel consumption isn't an issue.

[Smokydiesel]

Hi,

Thanks for the replies so far !

My 90 has an ex-Disco 200 tdi engine, ratio is 1:4 and I'm running on 7.50 x 16.

I swapped the old 2.5 NA engine for the TDI because I had read only positive reviews about this conversion.

To be honest I'm am a bit disappointed about the result;

Yes It does pull better than the old lump and yes it is faster, but together with all that came the extra engine noise and horrible body-vibrations while at idle speed.

To kill the noise I fitted the special thick rubber carpet-set on the floors and seatbox, and I stuck sound-foam on the inside of the bonnet.

I went through 3 sets of engine mounting rubbers to tackle vibrations.

I ended up buying those mounting rubbers by Glencoyne, that improved it a bit but it is still not perfect.

Had the injection pump and timing check.

There's noting rubbing against the body or chassis.

All in all, I'm a bit fed up with fiddling about without a good result.

As I'm only doing about 500 miles a year in the Defender, I started looking for a petrol engine.....

But reading your replies has made me re-think again.

It's true, Holland is about as flat as a pancake, but even here some extra power is more than welcome while pulling a trailer.

Ah well, might buy a v8 !!

Cheers,

Edwin